Atrium - The main room of a Roman house out of which one
had access to other parts of the house (see alae). There
were many types including ones that were completely
roofed (testudinate), ones with openings to the sky (compluvium),
which had, underneath the openings in the house floor,
as small rectangular depression to catch rainwater (impluvium).

Basilica - An important Roman building type consisting
of a large central hall often flanked by side aisles.
There were many variations.

Bipedales - Roman bricks measuring two Roman feet a
side.

Beed and Reel - A molding. A thin line of decorative
molding alternating between sets of beadlike elements
and cylindrical elements.

Bucrania - Decorative reliefs of the skulls or heads of
cattle or oxen. At times linked by swags of vegetal
motifs such as on the Ara Pacis.

Caldarium - The hot bath and 'sauna' of a Roman bath
complex.

Castrum - Fortress for any military purpose.

Clerestory - A level of wall above an arcade or loggia
in which windows allow light into a structure such as a
basilica.

Coffer - An inset decoration in a ceiling, vault, or
dome. They range from the undecorative types such as in
the inner dome of the Pantheon, to more ornate ones
decorated with moldings and rosettes.

Compluvium - The open roof of an atrium in a Roman house
(see impluvium, atrium).

Composite Capital (order) - An order consisting of a
hybrid of Corinthian and Ionic elements, normally with
the acanthus motifs of the Corinthian order surmounted
by Ionic volutes at the corners.

Cornice - The part of a building's entablature or roof
element, which projects away from the vertical of the
wall.

Cryptoporticus - Usually a slightly sunken arcade or
barrel vault creating a long walkway or storage area.
Architecturally, they often also function as buttressing
for larger, adjacent structures. Often lit by openings
piercing the upper part of the vault.

Curia - A governing body and name of the building which
housed it. The Curia was a meeting place for the Senate
or the town council of a Roman town.

Dentil - A molding consisting simply of a row of small
rectangles resembling teeth (hence, 'dentil'). Normally
found in ionic style entablatures under the cornice.

Domus - The Roman word for house. A single family
dwelling like many of those from Pompeii.

Egg and Dart - A molding consisting of an arrow-like
element alternating with an egg-shaped element.

Egg and Tongue - A molding consisting of a egg-shaped
element alternating with a downward pointing tongue.
Easily confused with egg and dart.

Entablature - The roof elements of a structure
consisting of the cornice, architrave and frieze.

Exedra - A semicircular niche or hemicycle.

Fascia - A molding simply of a thin, blank band.

Fauces - A small entry room of a Roman house, just as
one enters the front door. Leads to atrium.

Fornix - Older Roman term for an arch. Used also as a
description of an arch which is flanked by engaged
columns which in turn support an entablature above the
arch.

Forum - Main square or marketplace of a Roman town. In
Roman towns in Greek lands, the Greek term agora is
often used instead. The forum was often surrounded by
the most important governmental institutions such as a
curia building, temple to Jupiter Capitolium, basilica
or other such structures.

Frieze - The section of an entablature between the
cornice and the architrave. It can be decorated with
continuous reliefs (as in Ionic), divided into metopes
and triglyphs (as in Doric), or left plain or filled
with an inscription (as in the Corinthian favored by the
Romans).

Frigidarium - The cooling off pool in a Roman Bath
complex (do not confuse with natatio).

Guilloche - A decorative molding, usually used circled
around the top of a column base, of plaited or braided
elements.

Heliocaminus - Room in a Roman bath complex with large,
thermal windows used to gather heat from the sun.

Horrea - Roman warehouse.

Hypocausts - Small column-like elements used to support
a floor in the caldarium of a Roman bath complex. Hot
air from a furnace is pumped into the spaces around the
hypocausts and under the floor, thus heating the floor
and/or the water above.

Impluvium - In the atrium of a Roman house, the
depression in the floor below the compluvium or opening
in the roof which lets rainwater in. The water collects
in the impluvium.

Insula - An apartment style building with many domestic
units. Sometimes term is also used by archaeologists to
refer simply to a room designated by ruined walls.

Laconicum - Hot, dry room of a roman bath complex.

Lararium - The shrine area in a roman house, usually at
the back, where household gods are worshipped and their
images housed.

Macellum - A market structure furnishing meats and
poultry and other provisions.

Meta - The points where chariots turned in races in a
Roman circus (such as the Circus Maximus). The first
turn was called the meta prima, the second the meta
secunda.

Modillion - A sort of decorative bracket supporting the
cornice, normally with a double scroll motif.

Narthex - The enclosed portion of a church before the
nave; a sort of entrance area or covered porch.

Natatio - The swimming pool in a Roman bath complex.

Nymphaeum - A rocky outcrop or fountain house, either
natural or artificially made, which supplies water. The
sites were dedicated to the Nymphs.

Oculus - Circular opening in a roof or on a wall, such
as the oculus in the center of the dome of the Pantheon.

Odeion - (or Odeon) A small theater roofed off from the
sky, unlike theaters which were open air.

Oecus - The living room of a Roman house (domus).
Sometimes used as a dining room or for entertaining.

Orchestra - The circular area which functioned as a
stage for action in Greek theater. In the Roman theater,
scene structures and built up stages were created for
the action, and the circular orchestra was thus
truncated to a semi-circular area.

Palaestra - (or Palestra) A large square or rectangular
space, open to the air, surrounded by porticos held up
by rows of columns. Such structures were used for
athletic training and wrestling. At times associated
with Roman Bath complexes. Originally a Greek building
type.

Peristyle - A court or garden (as at Pompeii) surrounded
by porticos with columns.

Pilaster - Similar to an engaged column, but a
rectangular strip standing out slightly from a wall.

Podium - Roman temples were often raised up on high
masonry bases called podiums.

Pozzolana - A rust colored volcanic ash, found in the
regions in central Italy around the town of Pozzuoli,
which was a crucial component in Roman concrete.

Praetorium - The residence of the Governor of a Roman
province or Legion Commander.

Principia - In a Roman castrum or fortification where
the Standard of the Legion were kept. It was also a
place of meeting.

Quadriga - A four hourse chariot.

Quoins - Finished stones that construct the corner of a
building.

Rotunda - Domed building, circular in plan, such as the
Pantheon.

Spina - The center strip running down the middle of a
circus.

Sudatorium - Sweat room, steam room of a Roman bath
complex.

Taberna - A small shop.

Tablinum - A central room off the atrium of a Roman
house. Used as master bedroom.

Temenos - Sacred area surrounding a temple; temple
precinct, often walled off from surroundings.

Tepidarium - Warm bath of a Roman bath complex.

Tetrakionia - A monument with four architectural
elements placed at the crossing of two major street
intersections in a Roman town or city, as at Palmyra.

Tetrapylon - Also known as a quadrifronic arch. An arch
monument at a major street intersection which has two
vaults so people may pass through in all directions, as
at the ruined arch at Lepcis Magna.

Tribunal - A raised speaker's platform upon which a
general or emperor addressed the troops.

Triclinium - Dining area of a Roman house (domus),
consisting of three couch like platforms around the
three sides of the room upon which diners would recline.